Propeller



July, 5,1927.

H. MALM PROPELLER Filed Sept. 13. 1926 Z WJWJYW adv-.4406; ORN

Patented July 5, 1927.

UNITED STATES HENRY MALE, OF NEW YORK, N. Y.

PROPELLER.

Application fl'led September 13, 1926. Serial No. 185,082.

This invention relates to propellers for marine or other uses and comprises two or more blades extending radially from the hub .portion of the propeller; and the object of the invention is to provide a propeller of the class specified, the separate blades of which are provided at their inner or hub ends with projecting dove-tailed portions which flare outwardly from a shoulder portion adjacent said end of the propeller, and further to the provision of a plurality of teeth or project1ons spaced circumferentially on the beveled face of the projecting dovetailed member and occupying only a portion of the area of said beveled face; a further object being to provide a hub portion composed of separate parts divided transversely of the axis of the hub, said parts having on their adjacent faces when secured together, so dove-tailed recesses forming a socket within and between said parts to receive the dovetailed projecting members of the respective propeller blades; a further object being to provide the recesses in the separate parts of so the hub portion with annular grooves to receive the teeth or projections cooperating with the teeth or projections of said dovetailed projections to lock the propeller blades against rotation when in a given position of adjustment when the separate parts of the hub portion are secured together, it being understood that the interlocking teeth or projections on the hub portion and blade members are of such construction as to permit of the rotary adjustment of the propeller blades in the hub portion to regulate the pitch of the blades in different uses thereof; a further object being to provide a propeller construction of the class specified in which comparatively wide plain bearing faces are provided between the dove-tailed projections and the sockets of the hub portion to securely retain the parts against displacement and to hold the shoulder portions of the propeller blades in firm engagement with the flat outer faces of the hub portion.

The invention shown and described herein is an improvement on that shown and described in a prior application filed by me April 24, 1926, and bearing Serial No. 104,- 331, and is full disclosed in the following specification, 0 which the accompanying drawing forms a part, in which the separate parts of my improvementare designated till by suitable reference characters in each of the views, and in which 1 Fig. l is .a plan view of a propeller made according to my invention.

Fig. 2 is a partial section on the line 22 of Fig. 1.

Fig. 3 is a plan view of one part of a hub portion which I employ; and,

Fig. 4 is an enlarged detail view of the inner end portion of one of the propeller blades employed.

In Fig. 1 of the drawing, I have indicated a propeller consisting of three blade members 5, each ofwhich are of the same construction, and at 6 I have shown the hub portion of the propeller in connection with which the blades 5 are mounted. The hub portion 6 is composed of two parts 7 and 8 which are substantially of the same construction, each part having a bore 9 extending centrally therethrough to receive an engine or other bearing shaft in connection with which the propeller is to be mounted. The adjacent faces of the parts 7 and 8 .are provided with three dove-tailed recesses 10 j which open outwardl through fiat faces 11 on the periphery of t e separate parts 7 and 8 as clearly seen in Fig. 3 of the drawing. The recesses 10 of one part 7 register with the recesses 10 of the other part 8 when the separate arts are secured together by screws g5 12 passe throu h the part 7 and in threaded engagement wit the part 8 as seen at 13.

The recesses 10 are each rovided substantially centrally thereof wit annular grooves 14 in which are formed a series of teeth or 90 projections 15 adapted to cooperate with similar teeth or projections 16 extendin circumferentiall around the beveled face 1 of a dove-tailed projection 18 at the inner or hub end portions of the blades 5. It will be noted that the teeth or projections 16 enter the grooves 14 and mesh with the teeth or projections 15 in said grooves to provide means for keying or locking the blade members 5 against rotation in the sockets 10 of 100 the hub portion and et permit of rotar displacement of the b ade members 5 wit relation to the hub portion.

The comparatively wide surfaces 17' of the beveled face 17 disposed at opposite sides of the teeth or projections 16, and cooperating with "similar surfaces 10 in the recesses 10 provide strong and durable bearsurfaces between said parts and also reuse the wear on such surfaces.

It also be understood that in securseen at 19 in Fig. 2 of the drawing. I If any loosenessof the blades 5 should take place due to wear, this loosenessmay be taken up by tightening-the screws 12. However, the only wear which would take place wouldbe that due to adjustments of the parts, whlch would be very slight,

lit will he understood that While I have shown and described one method of carrying my invention into eifect, that I am not necessarily limited to the specific structure herein shown and described, and various changes therein and modifications thereof may be roadewithin the scope of the appended claims Without departing from t e spirit of invention or sacrificing its a L p/ JO 1s: eller, hub portion divided the axis thereof to form two arts, said parts having on adarranged about the periphportion, dove-tailed recesses, beveled faces of said recesses grooved, and teeth or projections in g ooved portions of said recesses.

9 a r cellar, hub portion divided transversely of the axis thereof to form two inent arts, said parts having on adces and arranged about the periphcry said hub portion, dove-tailed recesses, portions one beveled faces of said recesses grooved and teeth or projections in e giroover:

\ portions of said recesses, and rice having dovetailed PICOEEC etc-d be mounted in the recesses s, the beveled tacos of said dove i protections having circuinierentially so i l projections adapted to enter th the walls of said recesses, and co th the teeth or projections t ereby when the separate parts o ortion are secured together, said blades are retained against dis- 1 ll? '5.- l

. opeller, a hub portion divided tr er v of the axisthereof to form two independent parts, said parts having on adtaces arran ed about the e iphmembers on a neaaaeo cry of said. hub portion, dove-tailed recesses, ortions of the beveled faces of said recesses ing grooved and teeth or projections in the grooved portions of said recesses, propeller blades having dove-tailed projections adapted to be mounted in the recesses of said parts, the beveled faces of said dovetailed projections having circumierentially spaced teeth or projections adapted to enter the grooves in the walls of said recesses, and cooperating with the teeth or projections therein whereby when the separate parts of the hub portion are secured together, said propeller blades are retained against displacement, and said propeller blades having fiat shoulder portions adjacent the dovetailed projections and the hub portion, and flat outer surfaces in connection with which the shoulder portions operate.

4:. A propeller of the class described, the blades of which are provided at the hub end portions thereof with projecting dovetailed members on a part of. the beveled faces of which are arranged gear surfaces, the hub portion of the propeller being fashioned from independent parts between the adjacent faces oi which are formed dovetailed sockets to receive the dove-tailed members of the propeller blades, and the beveled faces of the sockets having annular grooves to receive the gear surfaces on said projecting members, and means in the grooved portions of the hub portion for engaging a predetermined nurnber oh the teeth of surfaces to prevent rotation of members in the hub portion when rate parts are secured together, 5. A propeller of the class d blades of which provided 1! portions thereof with projectin of the have which are arr nged gear s'u 1 portion of a propeller heir from indepen "it parts lootvo cent faces of which are torruou sockets to receive the dove bers or the propeller lolao beveled faces o1? he sockets lar grooves to receive the said projecti a members, grooved portion=- the hub pc gaging a predetermined ntunbe' oi the gear surfaces to prevent r the blade members in hub the separate pa ts are secured to all or, and said propeller blades and hub poi p E) cooperatuig n t surraces be brought into nrni engagement by lovetailed members in securing the parts of the hub portion togethern Q ll propeller oi the class do blades of which are provided at portions thereoi with projecting dos members on a oi the beveled which are gear the hub Iltlll l lll outer ends-0t which wit portion of the propeller being fashioned from independent parts between the adjacent faces of which are formed dove-tailed sockets to receive the dove-tailed members of the propeller blades, and the beveled faces of the sockets having annular grooves to receive the gear surfaces on said projecting members, means in the grooved portions of the hub portion for engaging a predetermined number of the teeth of the gear surfaces to prevent rotation of the blade members in the hub portion when the separate parts are secured together, said propeller blades and hub portion having cooperating flat surfaces adapted to be engagement by said dovetailed members in securing the separate parts of the hub portion together, and the adjacent faces of the separate parts of the hub portion being in spaced relation when the several parts of the propeller are assembled.

' 7. A. propeller of the class described, the blades of which are provided at the hub end portion thereof with projecting members, the

respect to the cenblades are of greater diameter than the inner end portions, said members having circumferentially spaced projections, the hub portion of the propeller being fashioned from independent parts between the adj acent'faces of which are formed sockets of a contour to snugly receive the projecting members of said blades, and said tral part of the brought into firm.

receive the projecand means in the hub for engaging a sockets havin grooves to tions on sai members, grooved portions of said predetermined number of said ro ections to prevent rotation of the blades m the hub portion when the separate parts are secured together.

8. A propleller of the class described, the blades of w ich are rovided at the hub end portion thereof wit projecting members; the outer ends of which with respectto the central part of the blades are of greater diameter than the inner end portions, said members having circumferentially spaced projections, the hub portion of the propeller being fashioned from independent parts between the adjacent faces of which are formed. sockets of a contour to snugly receive the projecting members of said blades and said sockets having grooves to receive tions on said members, means in the grooved portions of said hub for engaging a predeterminad number of said projections to prevent rotation of the blades in the hub ortion when the se arate parts are secure together, and sai propeller blades and hub portion having cooperatin fiat surfaces adapted to be brou ht into rm engagement in securing the bla es to the hub portion.

In testimony that I claim the foregoing as my invention I have signed my name this 9th day of September, 1926.

HENRY MALM.

the .projec 

